Michigan State coach Mike Tressel tries to pump up the defense after a Notre Dame score in the second half of the Spartans game against Notre Dame Saturday, Sept. 17, 2016 in South Bend, Ind. Dave Wasinger/Lansing State Journal

Michigan State defensive coordinator Mike Tressel gives an opening statement during a news conference for the NCAA Cotton Bowl college football game against Alabama, Sunday, Dec. 27, 2015, in Dallas. Brandon Wade AP

Head coach Mark Dantonio, left, and co-defensive coordinator Mike Tressel, work with their defense during the second half of the Spartans 24-7 victory over Maryland, Saturday, November 14, 2015 at Spartan Stadium in East Lansing. Dave Wasinger/Lansing State Journal

Co-defensive coordinator Mike Tressel congratulates safety Montae Nicholson after an interception in the fourth quarter of the Spartans 24-7 victory over Maryland, Saturday, November 14, 2015 at Spartan Stadium in East Lansing. Dave Wasinger/Lansing State Journal

Michigan State co-defensive coordinator Mike Tressel talks to the defense during the fourth quarter of the Spartans 30-10 win over the Chippewas at Spartan Stadium, Saturday, September 26, 2015. Dave Wasinger/Lansing State Journal

MSU defensive line coach Ron Burton, top, and co-defensive coordinator Mike Tressel yell instructions to the defense as Oregon makes a late run Saturday at Spartan Stadium in East Lansing. Rod Sanford/Lansing State Journal

Michigan State co-defensive coordinator Mike Tressel talks to members of the media Monday, August 10, 2015, during Media Day for the football team at Spartan Stadium. Dave Wasinger/Lansing State Journal

MSU co-defensive coordinators Harlon Barnett and Mike Tressel, background right, watch as Demetrious Cox upends Lawrence Thomas during Saturday’s spring game at Spartan Stadium. Spring practices are a time for teams to assess players’ skills and roles. Cox is battling for a starting position this fall at either cornerback or safety, while defensive lineman Thomas was being used as a fullback on the play during the scrimmage. Kevin W. Fowler/For the Lansing State Journal

Linebackers coach and co-defensive coordinator Mike Tressel talks with his plays during the Michigan State Spartans annual spring football game in April 2015 at Spartan Stadium in East Lansing. Eric Seals, Special to the Free Press

MSU assistant coach Mike Tressel works with the linebackers as the Spartans practice for the upcoming Cotton Bowl at the massive AT & T Stadium in Arlington, TX Sunday 12/28/2014. Next season, Tressel will be a co-defensive coordinator with Harlon Barnett. Rod Sanford/Lansing State Journal

MSU assistant coach Mike Tressel answers questions before the Spartans practice for the upcoming Cotton Bowl at the massive AT & T Stadium in Arlington, TX Sunday 12/28/2014. Next season, Tressel will be a co-defensive coordinator with Harlon Barnett. Rod Sanford/Lansing State Journal

EAST LANSING — It’s a position for which Mike Tressel has been groomed. The question is, where will Michigan State’s new defensive coordinator be inside Spartan Stadium come game day?

Tressel and Mark Dantonio will have that figured out when the lights come on for the season-opener against Utah State on Aug. 31. Until then …

“We’ll have him up and down and all around to try and figure it out,” Dantonio said. “It’s about where he’s most comfortable and where I’m most comfortable.”

After three seasons sharing the title with Harlon Barnett, who left in January to run the defense at Florida State, the longtime linebackers coach now takes over as Dantonio’s main defensive coordinator this season.

“The biggest difference will be on game days, when I’m solo making the calls and solo initiating the adjustments, although we have some great coaches that will be making the adjustments as well,” Tressel said during media day Monday. “I think that’s one of the biggest adjustments, because our staff does a great job of game-planning and practice planning and putting everything together."

And he does not yet know whether he plans to stay on the field, where he spent the past three years, or if he will replace Barnett in the booth — or follow Pat Narduzzi’s lead and split time with both, when needed.

But he also has learned along the way from both Narduzzi and Barnett about what it takes to make Dantonio’s defense tick.

“I guess all coaches will tell you that to be a great coach, you have to be yourself. You take bits and pieces from everybody you’ve worked with and seen have success. But ultimately, the players will realize you’re faking it if you’re not inclined to be yourself for the wrong reasons,” Tressel said. “I think I have Pat Narduzzi’s energy. Coach Dantonio definitely has a great defensive mind, and he was very analytical upstairs in the booth. He was able to separate himself a little bit from the chaos downstairs and be a little more calm and cool. And Harlon and I worked hand-in-hand, so you will see a lot of similarities to what you saw last year.”

From 2007-2014, when Narduzzi would storm the field in the second half like fire and brimstone raining from the press box above, the Spartans’ defense typically responded in kind to his passionate pleas.

Michigan State co-defensive coordinator Mike Tressel talks with players during first half action against Air Force on September 19, 2015.(Photo: Kirthmon F. Dozier, DFP)

Instead of allowing Narduzzi to poach either Tressel or Barnett when he left for the head coaching job at Pitt, Dantonio announced at the Cotton Bowl Classic after the 2014 season he would promote both to replace his longtime confidante.

“I think that has been a true extension of the leadership from coach Dantonio,” defensive tackles coach Ron Burton said. “Those guys understand his defense through and through, and I think that does not change when the next guy is elevated at that position. … You know the voice.

“If (we) have something we don’t understand, we’re going to coach D. But Mike — just as Harlon and coach Narduzzi did — involves everyone with the ability of what we want to get done and how we’re getting it done. I think that’s been a key factor for all of the guys that came before him and for him now.”

MSU ranked 26th in total defense in 2015, Barnett’s first year as a co-coordinator, and made the College Football Playoff. The Spartans ranked 32nd nationally in 2016 despite going 3-9 while allowing 158.7 rushing yards per game, which was 10th in the Big Ten.

Then with Barnett in the booth and Tressel on the field last season, the MSU’s defense experienced a second renaissance. The Spartans ranked No. 2 in the nation against the run (95.3 yards per game) and No. 7 in total defense at (297.6 yards). Just four opponents eclipsed 100 yards, and only national champion Alabama allowed fewer yards per game (94.7).

MSU also finished No. 17 in pass efficiency defense at 113.48, gave up the 10th-fewest first downs in the FBS and ranked 18th in third-down conversion defense at 32.8 percent.

“We’re certainly excited about the guys we have coming back and also about the depth,” Tressel said. “How many first-rounders do we have? Well, that’s yet to be determined. But there are an awful lot of guys that can be great Big Ten football players.”

Tressel also continues to maintain his position coach role with the linebackers, who now have to share his intensity with the rest of their defensive teammates.

“He’s able to get the whole room fired up just with his energy,” senior linebacker Andrew Dowell said. “We mess with him about how many cups of coffee he’s had before our meetings. He’s a really hype guy. …

“He’s not only a good coach, but coach Tressel knows how to teach you about the game and teach the game. Tons of guys on our defense can attest — they know different coverages now because that’s how he presents it in the meeting rooms and in our position rooms. Everybody is getting a better knowledge of the game of football, which is making us a better defense.”

Fifth-year senior linebacker Byron Bullough, who played for Narduzzi for one year, said he sees the similarities with Tressel. And he also believes the Spartans could see Tressel on the field at some point as well for more “enthusiasm, energy, intensity to the team.”

But it will ultimately be up to Dantonio, the architect of the defense and owner of a national championship ring from his time at Ohio State. And his own experience under Tressel’s uncle, Jim, will shape where Mike could be this fall.

“My experience as a defensive coordinator is when you’re up in the press box, the field is this big,” Dantonio said, shaping the size of a shoebox. “So when you get an 80-yard gain against you, there’s no panic. Even a 20-yard gain, there’s no panic. When you’re on the field and you see that ball go 15 yards, you go, ‘Whoa, that was a big gain!’ and it takes you out of your comfort zone a bit.